Goals: Mars Reconnaissance Orbiter (MRO) is designed to track changes in the water and dust in Mars' atmosphere, look for more evidence of ancient seas and hot springs and peer into past Martian climate changes by studying surface minerals and layering. The orbiter carries a powerful camera capable of taking sharp images of surface features the size of a beach ball. The orbiter also serves as a data relay station for other Mars missions.

Accomplishments: Among the mission's major findings is that the action of water on and near the surface of Mars occurred for hundreds of millions of years. This activity was at least regional and possibly global in extent, though possibly intermittent. The spacecraft has also observed signatures of a variety of watery environments, some acidic, some alkaline, which increase the possibility that there are places on Mars that could reveal evidence of past life, if it ever existed. MRO also broke data transmission records, surpassing all other previous Mars missions.

MRO's cameras not only capture Mars in high-definition; they also catch other Mars spacecraft in action. The image on the right is Phoenix descending to its landing site.

As of March 2010, MRO has sent back 100 terabits of data -- more than three times the amount of data from all other deep-space missions combined -- not just the ones to Mars, but every mission that has flown past the orbit of Earth's moon.